Push button assembly having an actuator subassembly fixed to the innerside of a face plate

ABSTRACT

A push button assembly having a halo which interfaces with a face plate opening, a halo adapter which interfaces the halo and an electrical switch, and a switch actuator carried by the halo and halo adapter which cooperatively nest to define an actuator housing within which the actuator is movable between first and second axial limits established by the halo and halo adapter, respectively. In a preferred embodiment, the halo also carries a push button identification plate within a single face plate opening.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates in general to push button assemblies, and morespecifically to modular push button assemblies which are easy toassemble and disassemble from the back of a push button face plate, inorder to replace damaged components and/or to change component colors,designs, configurations, identifying legends, and the like.

2. Description of the Prior Art

Push button assemblies used by the public, such as elevator call buttonslocated in elevator cars and in the hall ways of buildings, are subjectto abuse and components thereof must be periodically replaced. Also,even when the push button components are not damaged, it is oftennecessary to change identifying legends, and even functional componentsof the assembly itself, such as to accommodate changed building usage,to comply with new elevator codes, such as the handicap codes, or merelyto change the shape and/or color of certain of the push buttoncomponents which are visible to the public.

Since the changing of various elements of push button assembliesrequires the time of maintenance personnel, it is desirable and it is anobject of the present invention that such time be minimized by makingany and all components of a push button assembly quickly and easilychangeable without the necessity of using special tools or requiringspecial training or skills.

SUMMARY OF THE INVENTION

Briefly, the present invention is a new and improved push buttonassembly which is easy to assemble on the back side of a face plate, andjust as easily disassembled to change components thereof. The face plateincludes a single opening for each push button assembly, with the pushbutton assembly including a halo which interfaces the assembly with theface plate, snugly extending into the face plate opening. A halo adapterinterfaces the halo with an electrical switch which is actuatable viaaxial movement of a contact carrier. The halo and halo adapter nest tocooperatively define a housing for a switch actuator, eliminating theneed for special assembly and disassembly tooling. The halo and haloadapter define first and second axial travel limits for the switchactuator, respectively, with the electrical switch biasing the switchactuator to the first travel limit.

In a preferred embodiment of the invention, the halo also functions as apush button legend plate holder, having a legend holding portion whichis laterally offset from the portion which nests or cooperates with thehalo adapter to form the actuator housing. The legend plate snugly fitsinto a recess formed in the halo, and it has a fastener stud whichextends through an opening in the halo so that the plate can only beremoved by authorized personnel having access to the back of the faceplate. Thus, the legend plate function is provided without the necessityof punching and coining an additional opening in the face plate for eachlegend plate, as each push button assembly still requires only a singleopening in the face plate.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be better understood and further advantages and usesthereof more readily apparent, when considered in view of the followingdetailed description of exemplary embodiments, taken in connection withthe accompanying drawings in which:

FIG. 1 is a perspective view of a push button assembly which may beconstructed according to the teachings of the invention;

FIG. 2 is a cross sectional view of the push button assembly shown inFIG. 1, taken between and in the direction of arrows II--II,illustrating a first embodiment of the invention;

FIG. 3 is an exploded perspective view of the push button assembly shownin FIG. 2;

FIG. 4 is a perspective view of a pushbutton assembly constructedaccording to another embodiment of the invention;

FIG. 5 is an exploded perspective view of the push button assembly shownin FIG. 4; and

FIG. 6 is an exploded perspective view of selected elements of a pushbutton assembly constructed according to another embodiment of theinvention.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIGS. 1, 2 and 3 illustrate a push button assembly 10 constructedaccording to a first embodiment of the invention, with FIG. 1illustrating a perspective view of push button assembly 10 disposed in apanel or face plate 12, FIG. 2 being a cross sectional view thereof, andFIG. 3 being an exploded perspective view of push button assembly 10.Push button assembly 10 includes a halo 14, a halo adapter 16, a switchactuator 18, and an electrical switch 20. Halo 14, halo adapter 16, andswitch actuator 18 are formed of a high strength plastic, such as apolycarbonate. Electrical switch 20 is not shown in the cross sectionalview of FIG. 2, as the electrical switch may be any suitable switchhaving a contact carrier which is biased outwardly, and which isactuatable by a force directed axially inward. For purposes of example,it will be assumed that electrical switch 20 is the same switchdescribed in detail in U.S. Pat. No. 4,504,713, which is assigned to thesame assignee as the present application, and this U.S. Patent is herebyincorporated into the specification of the present application byreference.

Face plate 12 may be formed of any suitable material, such as steel, andit includes first and second major flat surfaces 22 and 24,respectively. The first and second surfaces 22 and 24 will be referredto as the outer and inner sides or surfaces, respectively, with theouter side being the side of the face plate 12 on which the push buttonassembly 10 may be actuated by a user. Face plate 12 includes an opening26 which extends between its major surfaces 22 and 24, and fastenermeans fixed to its inner surface 24 for securing the push buttonassembly 10 to the face plate 12, such as threaded studs 28 and 30 whichmay be stud-welded to surface 24. As illustrated, opening 26 in thefirst embodiment of the invention has a preferred substantially squareconfiguration. However, the teachings of the invention apply equally toother configurations, such as round, with the configuration of the faceplate opening usually being esthetically harmonious with theconfiguration of the actuating or visible portion of the associatedswitch actuating element 18.

Halo 14 and halo adapter 16 are constructed to nest snugly together toform a switch actuator housing 31 within which the switch actuator 18 isdisposed in a snug but axially slidable guided relationship relative tothe halo elements which cooperatively define the housing. Thus, theswitch actuator 18 may be quickly and easily assembled in its operativeposition without the use of special tools, and it may be just as easilydisassembled for repair and/or replacement of any of the halo elements14 or 16, or switch actuator 18.

In addition to functioning as an element of the switch actuator housing31, halo 14 interfaces the push button assembly 10 to the face plate 12,and halo adapter 16 interfaces the actuator housing 31 defined by haloelements 14 and 16 to the electrical switch 20.

As best shown in the exploded perspective view of FIG. 3, which alignsthe various elements of the push button assembly 10 along a longitudinalaxis 32 which extends along the actuating axis of movement of the pushbutton assembly 10, halo 14 includes an intermediate flange 34 having afirst flat surface 36 which faces the face plate 12 and a second flatsurface 38. An axial opening 40, having a substantially squareconfiguration in this embodiment of the invention, extends between theaxial ends of halo 14. First and second projections 42 and 44 extendoutwardly from the first and second flat surfaces 36 and 38,respectively, with the projections 42 and 44 surrounding opening 40. Thefirst projection 42 is configured to snugly enter opening 26 in the faceplate 12. The depth of projection 42 may be selected to be substantiallyequal to the thickness of the face plate 12, such as when vandalism maybe a problem, with the flat surface 46 at the axial end of projection 42and the first major surface 22 of the face plate 12 being in a commonplane. In installations where vandalism is not expected to be a problem,the depth of projection 42 may be selected for decorative effect, e.g.,it may exceed the face plate thickness.

Halo adapter 16 has surfaces 48 and 50 which define first and secondaxial ends, respectively, first and second upstanding sides 52 and 54,respectively, and top and bottom portions 56 and 58, respectively.Mounting ears 60 and 64 having stud receiving openings 66 and 68,respectively, extend outwardly from the top and bottom portions 56 and58, respectively. A recess or opening 70 having a substantially squarecross sectional configuration extends inwardly from the first axial end48 to a wall portion 72. Wall portion 72 is spaced a small dimensionfrom the second axial end 50 to define a shallow opening or recess 73best shown in FIG. 2. Wall 72 has a central opening 74 so light from alamp associated with electrical switch 20 may illuminate the switchactuator 18, on illuminated embodiments of the invention, such as thelamp 76. Wall 72 further defines four like configured and dimensionedadditional openings 78 symmetrically disposed about central opening 74,for receiving switch actuating elements or legs 80 of the switchactuator 18, as will be hereinafter explained.

Switch actuator 18, which is the "button" of the assembly 10, includes abase or flanged guide portion 82 having surfaces 84 and 86 which definefirst and second axial ends, respectively, and an actuating portion 87which includes a projection 88 which extends outwardly from the firstaxial end 84. The hereinbefore mentioned actuating legs 80 extendoutwardly from the second axial end 86. A lens or crystal 90 completesthe actuating portion 87, with crystal 90 being suitably fixed to theprojection 88, such as by ultrasonic welding. The guide base 82 andcrystal 90, as hereinbefore stated, are each formed of a suitable highstrength plastic, such as a polycarbonate, and in illuminatedembodiments they are transparent or translucent to transmit light toindicate to the user that the button has been actuated, e.g., that anelevator call has been registered, when the push button assembly 10 isused in an elevator application. The projection 88 and crystal 90 aredimensioned and configured to snugly but slidably enter square opening40 in halo 14, and the outer configuration and dimensions of base orguide flange 82 are selected such that flange 82 snugly but lidablyenters square opening 70 in halo adapter 16. The actuating legs 80 aredimensioned and positioned to snugly but slidably enter openings 78 inwall 72 of halo adapter 16.

In the assembly of the switch actuator 18 into the housing 31 defined bythe nested halo elements 14 and 16, actuator 18 is dropped into opening70 in halo adapter 16 such that the actuating legs 80 enter openings 78.The projection 44 on halo 14 is then advanced into opening 70, with theadjacent surfaces snugly fitting together such that they frictionallyengage to define the actuator housing 31 for switch actuator 18. Thissub-assembly of nested halo elements, which includes the captured switchactuator 18, may then be frictionally engaged with the electrical switch20. For example, switch 20 may have tabs 92 at its first axial end 94which snugly enter recess 73 at the second axial end 50 of halo adapter16. Actuating legs 80 engage the spring biased contact carrier 96 ofswitch 20 and the contact carrier 96 thus biases switch actuator 18 to afirst axial stop defined by halo 14, i.e., the surface 84 of actuator 18which defines the first axial end contacts surface 38 at the secondaxial end of the flange 34.

An actuating force applied to crystal 90 of the actuator 18 overcomesthe bias of the electrical switch 20, and legs 80 force the contactcarrier 96 axially inward to the actuated position of electrical switch20. Switch 20 may have any desired number of normally open or normallyclosed contacts. Actuator 18 can only be forced to a second axial limitdefined by halo adapter 16, i.e., the surface 86 which defines thesecond axial end of the base or guide flange 82 contacts wall 72 of haloadapter 16.

Switch 20 has mounting ears 98 and 100 having stud receiving openings102 and 104, respectively, which openings are aligned with studs 28 and30 and stud receiving openings 66 and 68 in the halo adapter 16. Nuts106 and 108 engage studs 28 and 30 to complete the fastening function.

FIGS. 4 and 5 illustrate a push button assembly 110 constructedaccording to a second embodiment of the invention which includes anidentification legend plate 111 disposed to the left of the actuatingbutton, with reference to the user of the push button assembly 110. FIG.4 is a perspective view of push button assembly 110 disposed in a panelor face plate 112, and FIG. 5 is an exploded perspective view of pushbutton assembly 110.

Push button assembly 110 includes a halo 114, a halo adapter 116, aswitch actuator 118, and an electrical switch. The electrical switch isnot shown in FIG. 5, as it may be identical to the switch 20 shown inFIG. 3.

Face plate 112 includes first and second major flat surfaces 122 and124, respectively, and a single opening 126 for each push buttonassembly 110, which opening extends between its major surfaces. Fastenermeans, such as threaded studs 127, 128, 129 and 130 are secured to thesecond major surface 124, such as by stud-welding, for the purpose ofsecuring push button assembly 110 to the face plate 112.

Similar to the first embodiment of the invention, the halo elements 114and 116 next snugly together to define a switch actuator housing 131.Switch actuator 118 is slidable in housing 131 between first and secondaxial limits respectively defined by the halo 114 and the halo adapter116. Also similar to the first embodiment, halo 114 functions tointerface the push button assembly 110 to the face plate 112, and thehalo adapter 116 functions to interface the actuator housing 131 to theelectrical switch 20.

The exploded perspective view of push button assembly 110 in FIG. 5aligns the various elements of the assembly 110 along a longitudinalaxis 132 which extends along the actuating axis of the push buttonassembly 110. In this embodiment of the invention, halo 114 has anelongated, generally rectangular configuration having squared ends and alongitudinal axis 125 which extends between the ends. For purposes ofdescription, the elongated configuration of halo 114 will be equallydivided into first and second sections 133 and 135, respectively, onopposite sides of a vertical bisecting axis 137. The first or right handsection 133 is associated with the actuating housing 131 in a mannersimilar to the first embodiment of the invention, and the second or lefthand section 135 forms a mounting structure for supporting the legendplate 111.

Halo 114 includes an intermediate flange 134 having a first flat surface136 which faces the face plate 112 and a second or opposed flat surface138. An axial opening 140 in the right hand section 135, which has asubstantially square configuration in this embodiment, extends betweenthe axial ends of halo 114. First and second projections 142 and 144extend outwardly from the first and second flat surfaces 136 and 138,respectively, with a right hand portion of projection 142 and projection144 surrounding opening 140. The first projection 142 is configured tosnugly enter opening 126 in the face plate 112. The flat surface 146 atthe first axial end of projection 142 and the first major surface 122 ofthe face plate 112 may be in a common plane, or displaced from the planeof surface 122, as desired.

The second or left hand section 135 of the halo 114 is recessed inwardlyfrom the axial end of projection 142 to define a recess 147 forreceiving legend plate 111. The left hand section 135 further includes acentrally disposed opening 149 which extends between the recess 147 andthe second side 138 of flange 134, and mounting ears 151 and 153 whichextend outwardly from flange 134. Mounting ears 151 and 153 haveopenings 155 and 157 for receiving studs 127 and 129, respectively.

The legend plate 111 has first and second major surfaces 159 and 161,respectively, with the first surface 159 having an identifying legend163, which may include braille, as illustrated. The identifying legend163 projects outwardly from the first major surface 159. The secondmajor surface 161 has a threaded stud 165 attached thereto. Legend plate111 is relatively thin, with recess 147 having a depth which ispreferably substantially equal to the thickness dimension of plate 111,in order to place the first major surface 159 of the legend plate intothe same plane as the surface at the axial end of projection 142.

Legend plate 111 fits snugly into recess 147, with the threaded stud 165extending through opening 149. Suitable fastener means are provided forsecuring plate 111 in the recess 147, such as an elongated bar 167having an opening 169, and a nut 171. Bar 167 is longer than thediameter of opening 149, and the diameter of opening 169 exceeds thediameter of stud 165. Thus, the bar 167 is dropped over stud 165 and nut171 engages stud 165 to firmly secure the legend plate 111 in the recess147 of halo 114.

Halo adapter 116 may be constructed and dimensioned the same as the haloadapter 16 of the first embodiment, and thus need not be described indetail. Like reference numerals in FIGS. 3 and 5 indicate like portionsof the halo adapters 16 and 116.

Switch actuator 118 has the same functional parts as the switch actuator18 shown in FIG. 3, and is thus not described in detail. Like referencenumerals in FIGS. 3 and 5 indicate like portions of the switch actuators18 and 118.

In the assembly of switch actuator 118 into the housing 131 defined bythe halo elements 114 and 116, the actuator 118 is dropped into opening70 in the halo adapter 116 such that the square guide flange 82 isguided by the side walls of the square opening 70 and the actuating legs80 enter openings 78. The second projection 144 of halo 114 is thenpressed into opening 70 of the halo adapter 116 such that theyfrictionally engage to define the actuator housing 131. Thissub-assembly of nested halo elements which includes actuator 118 maythen be frictionally engaged with switch 20 as hereinbefore describedrelative to the first embodiment of the invention. The assembled pushbutton assembly 110 may then be positioned in opening 126 of the faceplate, with studs 127 and 129 entering openings 155 and 157 in themounting ears 151 and 153 of the halo 114. Nuts 173 and 175 secure theleft hand side of halo 114 to the face plate 112. Studs 128 and 130enter the openings in the mounting ears of the halo adapter 116 and theelectrical switch 20, as hereinbefore described, and nuts 106 and 108complete the fastening function, tightly clamping the right hand side ofhalo 114 between the face plate 112 and the halo adapter 116, whilefastening the remaining components of the push button assembly 110 tothe face plate 112.

While push button assembly 10 illustrates actuator button 18 with asquare configuration, and push button assembly 110 illustrates thelegend plate 111 and actuator button 118 with substantially squareconfigurations, which are preferred embodiments of the invention, theymay have other configurations, such as round. A round embodiment of theinvention with a round braille legend plate is set forth in FIG. 6,which is an exploded perspective view of a push button assembly 210.Only a halo 214, a legend plate 211 and an actuator 218 are shown inFIG. 6, as the associated halo adapter may be the same as the haloadapters 16 and 116, best shown in FIGS. 3 and 5, respectively, and theassociated electrical switch may be the same as electrical switch 20.The associated face plate is not shown as it would simply have a singleopening for each push button assembly 210 sized to snugly acceptprojection 242 on halo 214.

Switch actuator 218 has a round actuating portion 287 which includes aprojection 288 and a crystal 290, and a substantially square guideportion or base 282.

Halo 214 has an elongated projection 242 having first and second ends,and a longitudinal axis 225 which extends between the ends. In thisembodiment the ends are in the shape of half circles, i.e., theelongated projection 242 has first and second integrally connectedcurved portions 233 and 235, respectively, in which the first curvedportion 233 defines a round opening 240 for cooperating with the roundactuating portion 287 of the switch actuator 218. The second curvedportion 235 defines a round recess 247 for snugly receiving the roundlegend plate 211.

The associated halo adapter is the same as halo adapters 16 and 116, andthus has a square recess or opening 70 for cooperation with the squareguide portion or base 282 of the switch actuator 218.

The other portions of halo 214, actuator 218 and legend plate 211 may bethe same as described relative to the embodiment shown in FIGS. 4 and 5.

We claim as our invention:
 1. A push button assembly, comprising:a halo;said halo having first and second sides, a first opening which extendsbetween said first and second sides, and first and second projections onsaid first and second sides, respectively, which surround said firstopening, a halo adapter; said halo adapter having first and secondsides, a recess, and a wall portion, with said recess extending inwardlyfrom the first side, terminating at said wall portion which is adjacentto the second side, said halo adapter being nested with said halo, withthe second projection on the halo extending into the recess of the haloadapter, a switch actuator captured between said nested halo and haloadapter to define a subassembly in which said switch actuator is movablebetween first and second axial limits defined by said halo and haloadapter, respectively, an electrical switch snugly engaging said haloadapter and biasing said switch actuator to said first axial limit, saidswitch actuator being accessible via the first opening in said halo formovement to said second axial limit and simultaneous actuation of saidelectrical switch, a face plate having inner and outer major sides andan opening which extends between said sides, said halo being snuglydisposed in said face plate opening, with the first projection of saidhalo extending into the face plate opening, and with said switchactuator being accessible on the outer major side of said face plate,and means fixing said subassembly and said electrical switch to theinner side of said face plate, whereby the halo and halo adapter areboth stationary, and access is required to the inner side of said faceplate to disassemble said subassembly.
 2. The push button assembly ofclaim 1 including:a second opening in the halo, laterally spaced fromthe first opening, a recess surrounding said second opening, a pushbutton identifying legend plate in said recess, and fastener means whichextends through said second opening for securing said legend plate insaid recess, said legend plate being displayed on the outer major sideof the face plate, adjacent to the switch actuator.
 3. The push buttonassembly of claim 2 wherein the halo and the legend plate have surfacesdisposed in a common plane which are visible on the outer major side ofthe face plate.
 4. A push button assembly, comprising:a halo, a haloadapter nested with said halo, said halo adapter having first and secondsides, a recess, and a wall portion, with said recess extending inwardlyfrom the first side, terminating at said wall portion which is adjacentto the second side, a switch actuator captured between said nested haloand halo adapter, and movable between first and second axial limitsdefined by said halo and halo adapter, respectively, an electricalswitch snugly engaging said halo adapter and biasing said switchactuator to said first axial limit, a first opening in said halo viawhich said switch actuator is accessible for movement to said secondaxial limit and simultaneous actuation of said electrical switch, a faceplate having inner and outer major sides and an opening which extendsbetween said sides, said halo having first and second sides, and firstand second projections on said first and second sides which surround thefirst opening, the first projection on said halo being snugly disposedin said face plate opening, with said switch actuator being accessibleon the outer major side of said face plate, and with the secondprojection on said halo extending into the recess of the halo adapter,and means fixing said nested halo and halo adapter, and said electricalswitch, to the inner side of said face plate, said means fixing saidnested halo and halo adapter, and the electrical switch to the faceplate including studs fixed to the inner side of the face plate andmounting ears integral with the halo adapter having stud receivingopenings, with the halo being clamped between the face plate and thehalo adapter.
 5. A push button assembly, comprising:a halo, a haloadapter nested with said halo, said halo adapter having first and secondsides, a recess, and a wall portion, with said recess extending inwardlyfrom the first side, terminating at said wall portion which is adjacentto the second side, a switch actuator captured between said nested haloand halo adapter, and movable between first and second axial limitsdefined by said halo and halo adapter, respectively, an electricalswitch snugly engaging said halo adapter and biasing said switchactuator to said first axial limit, a first opening in said halo viawhich said switch actuator is accessible for movement to said secondaxial limit and simultaneous actuation of said electrical switch, a faceplate having inner and outer major sides and an opening which extendsbetween said sides, said halo having first and second sides, and firstand second projections on said first and second sides which surround thefirst opening, the first projection on said halo being snugly disposedin said face plate opening, with said switch actuator being accessibleon the outer major side of said face plate, and with the secondprojection on said halo extending into the recess of the halo adapter,and means fixing said nested halo and halo adapter, and said electricalswitch, to the inner side of said face plate, said wall portion of thehalo adapter defining guide openings, said switch actuator having firstand second ends, with the first end being accessible for actuation onthe outer side of the face plate, and with the second end havingprojections which extend through said guide openings and engage theelectrical switch.
 6. A push button assembly, comprising:a halo, a haloadapter nested with said halo, a switch actuator captured between saidnested halo and halo adapter, and movable between first and second axiallimits defined by said halo and halo adapter, respectively, anelectrical switch snugly engaging said halo adapter and biasing saidswitch actuator to said first axial limit, a first opening in said halovia which said switch actuator is accessible for movement to said secondaxial limit and simultaneous actuation of said electrical switch, asecond opening in the halo, laterally spaced from the first opening, arecess surrounding said second opening, a push button identifying legendplate in said recess, fastener means which extends through said secondopening for securing said legend plate in said recess, a face platehaving inner and outer major sides and an opening which extends betweensaid sides, said halo snugly disposed in said face plate opening,displaying said legend adjacent to said switch actuator on the outermajor side of said faceplate, and means fixing said nested halo and haloadapter, and said electrical switch, to the inner side of said faceplate, said legend plate being displayed on the outer major side of saidface plate, adjacent to the switch actuator, said means fixing thenested halo and halo adapter, and the electrical switch to the faceplate including studs fixed to the inner side of the face plate, andfirst and second pairs of mounting ears integral with the halo and haloadapter, respectively, having stud receiving openings, with the halohaving a first portion directly clamped to the face plate via said firstpair of integral mounting ears and a second portion clamped to the faceplate by the halo adapter and said second pair of integral mountingears.
 7. A push button assembly, comprising:a halo, a halo adapterhaving a square configuration, said halo and said halo adapter beingnested to define an actuator housing, a switch actuator disposed in saidactuator housing, captured between said nested halo and halo adapter,and movable between first and second axial limits defined by said haloand said halo adapter, respectively, said halo being an elongatedstructure defining a rectangular configuration having first and secondends and a longitudinal axis which extends between said ends, with therectangular configuration being comprised of first and second integrallyconnected square portions, with the first square portion of said halobeing nested with the halo adapter to define a square actuator housing,and with said actuator having a square configuration for snug butslidable movement between the axial limits defined by the actuatorhousing, an electrical switch snugly engaging said halo adapter andbiasing said switch actuator to said first axial limit, a first openingin said halo via which said switch actuator is accessible for movementto said second axial limit and simultaneous actuation of said electricalswitch, a second opening in said halo, a recess surrounding said secondopening, a push button identifying legend in said recess, fastener meanswhich extends through said second opening for securing said pushidentifying legend in said recess, a face plate having inner and outermajor sides and an opening which extends between said sides, said halosnugly disposed in said face plate opening, displaying said legendadjacent to said switch actuator on the outer major side of saidfaceplate, and means fixing said nested halo and halo adapter, and saidelectrical switch, to the inner side of said face plate, said meansfixing the nested halo and halo adapter, and the electrical switch tothe face plate including studs fixed to the inner side of the faceplate, and mounting ears on the second square portion of the halo and onthe halo adapter having stud receiving openings for receiving the studsattached to the face plate.